Thanks MSEBerg, checked out the Note. We've been able to duplicate between these two machines via ASM before though, which is what's disconcerting.

I would like to understand why it's failing on a Duplicate considering I'm not asking it to look for SPFILE from autobackup as autobackup is OFF in the Rman env settings for ECPMT (Prim). Also, for the Primary database Rman settings (source database being cloned), should this setting be pointing to a standby directory?

CONFIGURE SNAPSHOT CONTROLFILE NAME TO '+DG_01/ecpmtsb/controlfile/';

This worked the other day for my colleagues using the same RMAN script, then to make sure it was a solid procedure, we blew away the instance and files and now it's not allowing us to do the duplicate claiming to not be able to access AUTOBACKUP files.

Any help or input Mseberg would be incredibly appreciated. Thank you !